Valve for oil well swabs



July 20, 1943- R. B. FRASER VALVE FOR OIL WELL SWABS INVIENTOR. P055675. HQASE/Q Arnau/55g vavoid overloads.

Patented July 20, 1943 UNITED STATES PATENT OFFICE A f 2,324,689

VALVE FOR OIL WELL SWABS Robert B. Fraser, Ventura, Calif. ApplicationDecember 19, 1.940, Serial No. 370,778

(ci. 251-118) i 4 Claims. My invention relates to a Valve for a wellparticularly adapted for oil wells. One ofrthe principal objects of'thisinvention is to provide a well swab valve of this class for cleaning oilwell casings or tubings without employing exterior rubber members orother readily deleterious members.

Another important object of this invention is to provide a'well swabvalve of this class having operating members which will not readilydeteriorate or get out of order, and one which may be readily`disassembled and in which the various elements are `readily accessible.

An important object also of this invention is to provide a well swabvalve of this class which may be easily operated, which may be loweredswab,

`into or raised from the well with considerable speed, and which willoperate automatically to A further object of this invention is toprovide a well swab valve of this class which may not be readily damagedby sudden operation or movement in either direction. f V

With these and other objects in (View, as will yappear hereinafter, Ihave devised a Well swab valve having certain novel features ofconstrue# claims, reference being had to the accompanying drawing, andto the characters of reference thereon, which form apart of thisapplication, in which:

Fig. 1 is a fragmentary elevation of an oil well showing my well swab,in one form, in position therein;

Fig. 2 is a fragmentary` longitudinal sectional view thereof; and,

Figs. 3 and 4 are transverse sectional views thereof, taken,respectively, through 33, and 4-4 of Fig. 2.

The oil well casing, designated I, and in which my device is used, issubstantially of uniform inside diameter. My well swab is constructed tot substantially the inside of the casing for cleaning or swabbing thesame.

The housing or casing of my swab, as shown in the drawing, may consistof a rope socket member II, an upper tubular casing I2, a lower tubularcasing I3, an upper tube or pipe length or section I4, connecting thecasing I2 to the rope socket member, a lower tube or pipe section I5,extending below the casing I3, and a lower guide or end piece I6 securedto the lower end of the Pipe section l5. The pipe sections I4 and I5 areadded principally for the purpose of adding weight.

All of these members'mayb'e only one-eighth of an inch less in diameterthanlthe inside diameter ofthe well casing I. On the upper tubularcasing I2 is provided a pair of `spaced sealing vided a cylinder member3I which'may be pressed therein and engages at its lower' end an annularshoulder I3? near the upper end of the casing I3. Within and atthe axialportion of the cylinder member 3| is reciprocally mounted a piston 32which is so movablewithin the cylinderltha't its ends are extensiblebeyond the ends thereof, as lwill be described` hereafter.

of the inner wallof thevcyli'ndernmember vmay be iluted, as indicatedby`3l and 3Ib. If desired, the upper end of the piston may also belongitudinally fluted, as indicated by 32a. This piston :is providedintermediate its ends with spaced sealing rings 33 so that the portionbetween the `rings may be sealed with respect to the opposite Vends ofthe cylinder member,

Within the casing I3 Vis a compression spring 4I whichis seated at itslower end on a shoulder I3b of the casing. At the upper end of thespring is a washer 42 which is adaptedto `engage the lower end ofthecylinder member to limit the upward movement of the spring to a positionbelow the lower end of the cylinder member 3l. This washer 42 isprovided with ports near the periphery, that is, radially outwardly fromthe central portion, which central portion is engageable by the piston,Thus, the spring 4I is permitted to act directly upon the piston andforce the same ush with the lower end of the cylinder member.

Within the casing I2 is a stop or anvil 5I which is circular in form andrests upon an annular shoulder I2a. This anvil is forced against theshoulder from the upper side by a spring 52 which is held in position bya transverse pin 53.

The guide or lower end piece IE, which is se- The opposite ends cured tothe lower end of the casing I3, or, as shown, to the lower end of thepipe section I5, has an axial bore extending to its lower end. When thestring is lowered into the well, a screw plug 6I is screwed into thelower end of the guide or end piece, as indicated by dotted lines inFig. 2. As soon as liquid in the well is encountered, and the depththereof is noted, the string is withdrawn and the screw plug 6| removed.

The swabbing operation is then begun. The string is again lowered intothe well, to the desired depth below the surface of the liquid. Suchlowering causes the piston 32 to be raised. But the anvil 5I stops suchupward movement, the spring 52 taking the recoil. Continued lowering ofthe string will allow the liquid, mud, and the like, to by-pass thepiston, through the longitudinal utes 3la, and to flow out at the topthrough openings Ila in the rope socket, the

latter openings radiating from the bore of the rope socket member, andare directed upwardly at an angle. As the string is raised, the materialto be cleaned from the well enters the interior of the casing l2 throughthe transverse openings Ila. Raising of the well swab causes the pistonto return to its normal lower sealing position, shown by solid lines inFig. 2. When the load within the swab becomes too great, the piston 32is forced down beyond said normal position and is permitted by thespring 4| to recede, until the flutes 3|b at the lower end of thecylinder member, or the utes 32a at the upper end of the piston, orboth, allow the excess liquid, mud, or the like, to by-pass the piston,and to pass through the lower end of the casing I3 and the end piece I6back into the well below the swab. Such action prevents overloading ofthe rope, and serves as a safety means.

Though I have shown and described a particular construction,combination, and arrangement of parts and portions of my well swabvalve, I do not wish to be limited to the same, but desire to include inthe scope of my invention the construction, combination, and arrangementsubstantially as set forth in the appended claims.

I claim:

1. In a well swab, a cylinder open at the upper and lower portions, atubular casing for supporting the cylinder, a piston reciprocallymounted within the cylinder, the cylinder and piston being soconstructed as to provide by-pass means between the cylinder and pistonwhen the latter is at either end of its stro-ke, a single spring forurging the piston upwardly to an intermediate position in which thecylinder is sealed by the piston, and a resilient bumper for limitingthe upward, opening movement of the piston.

2. In a means of the class described, a tubular casing, a tubularcylinder within the casing, a piston reciprocally mounted within thecylinder,

the lower portion of the inner wall of the cylinder having longitudinalflutes, a stop washer, and a spring positioned in the casing below thecylinder for urging the washer against the cylinder at the lower ends ofthe iluted portion thereof, said washer having openings communieatingwith the lower ends of the flutes, the piston being adapted normally torest upon the central portion of the washer to close the bore of thecylinder.

3. In a means of the class described, a tubular casing, a tubularcylinder within the casing, a piston reciprocally mounted within thecylinder for closing the bore thereof, the upper portion of the innerwall of the cylinder having longitudinal utes, means for limiting thelower position of the piston, a spring positioned within the casingabove the cylinder, means for limiting the movement of the upper end ofthe spring within the casing, a perforated washer, there being providedan annular shoulder in the casing above the cylinder, the spring beingadapted to urge the washer against the shoulder, the upper end of thepiston being normally spaced below the washer, the piston being capableof being forced upwardly with its upper end above the cylinder andadapted, when so moved, to engage the central portion of the washer andunseat said washer from said shoulder against the force of said springand open the bore of the cylinder.

4. In a means of the class described, a tubular casing, a tubularcylinder within and at the intermediate portions of the casing, a pistonreciprocally mounted within the cylinder, the lower and upper portionsof the inner wall of the cylinder having longitudinal flutes, a stopwasher, a spring positioned in the casing below the cylinder for urgingthe washer against the cylinder at the lower ends of the iluted portionthereof, said washer having openings communicating with the lower endsof the ilutes, the piston being adapted to rest upon the central portionof the washer to close the bore of the cylinder, a second springpositioned within the casing above the cylinder, means for limiting themovement of the upper end of the latter spring within the casing, aperforated washer, there being provided an annular shoulder in thecasing above the cylinder, the latter spring being adapted to urge thelatter washer against the shoulder, the upper end of the piston beingnormally spaced below the latter washer, the piston being capable ofbeing forced upwardly with its upper end above the cylinder and adapted,when so moved, to open said bore and to engage the central portion ofthe latter washer and unseat the same from said shoulder against theforce of said spring.

ROBERT B. FRASER.

